powerpc: remove interrupt handler functions from the noinstr section

The allyesconfig ppc64 kernel fails to link with relocations unable to
fit after commit 3a96570f ("powerpc: convert interrupt handlers to
use wrappers"), which is due to the interrupt handler functions being
put into the .noinstr.text section, which the linker script places on
the opposite side of the main .text section from the interrupt entry
asm code which calls the handlers.

This results in a lot of linker stubs that overwhelm the 252-byte sized
space we allow for them, or in the case of BE a .opd relocation link
error for some reason.

It's not required to put interrupt handlers in the .noinstr section,
previously they used NOKPROBE_SYMBOL, so take them out and replace
with a NOKPROBE_SYMBOL in the wrapper macro. Remove the explicit
NOKPROBE_SYMBOL macros in the interrupt handler functions. This makes
a number of interrupt handlers nokprobe that were not prior to the
interrupt wrappers commit, but since that commit they were made
nokprobe due to being in .noinstr.text, so this fix does not change
that.

The fixes tag is different to the commit that first exposes the problem
because it is where the wrapper macros were introduced.

Fixes: 8d41fc61

 ("powerpc: interrupt handler wrapper functions")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Slightly fix up comment wording]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210211063636.236420-1-npiggin@gmail.com